A silicone compound is applied to various fields such as detergent, finisher, fiber-treating agent and lubricant, and particularly a finisher for textile products such as clothes is widely used for the purpose of conferring an effect of improving the feel of an object. Many techniques of using a silicone compound in combination with a polymer compound are also disclosed. JP-A 2000-129570, JP-A 2000-129577, JP-A 2000-129578, JP-A2000-239970, JP-A2003-89978, JP-A5-239774, JP-A 8-260356, JP-A 9-13272, JP-A 9-111662, JP-A 11-229266, JP-A 10-508911, JP-A 10-508912 and JP-A No. 5-44169 disclose respectively a fiber-treating agent composition containing both a water-soluble polymer compound generally known as a starch base and a silicone compound. WO-A 00/73351 discloses a specific polysaccharide derivative, and it is described that the polysaccharide derivative in WO-A 00/73351 can stabilize hydrophobic compounds.